Regulating system



' 1,633 11 June 28,1927. Lu W THOMPSQN 3 REGULATING SYSTEM Filed April21, 1924 Inventor; Louis W Thompson His Attorney.

mama June 28,1927.

UNITED STATES PATENT "OFFICE. p

LOUIS W. THOIPSON, OF SOHENEGTATJY, NEW YORK, ASSIGNOB 130 GENERAL mo-.lBIG COMPANY, A CORPORATION OF NEW YORK.

' BIG'U'LATING SYSTEM.

i am filed April 21, 19334. Serial no. 707,350,

My invention relates to regulating Systems, and hasfor its object theprovislon of an improved regulator which comprises an anti-huntingdevie'of rugged and simple construction.

It is customary to provide a regulator with anti-hunting means designedto eliminate eriodic pulsations or changes in an electrical condition ofthe circuit to be controlled. In the past these anti-hunting means havecomprised a relay or a relay are operated to control the efiective fieldre-' slstance of the exciter. I

I have shown two electron dischar e tubes 12 and 13 associated with thesecon ary 14 of the transformer 10. It will be ap a'rent. however, thattwo tubes are require only where it is desired to rectify both sides of65 the alternatin current wave and thus' to" avoid inoperatlveness ofthe regulating apparatus, due to failure of one of theftubes.) The tubes12 and 13 are provided with coil arranged to anticipate and obviate theplates and 16 respectively and with fila 60 production of a conditionapt to produce periodic pulsations in voltage and current of 15 thecircuit to be regulated. In accordance with my invention, the use ofsuch a relay or relay coil is rendered unnecessary and the constructionof the regulator as a whole is greatly simplified.

My lIlVGIltlOIhWlll be better understood on reference to the followingdescription when considered in connection with the accompanying drawingand its scope will .be pointed out in the appended clalms. Referring tothe rawing, the single figure thereof is a diagrammatic showing ofa'regulating system wherein my invention has been embodied.

The drawing shows an alternating current machine 1, comprising-a fieldwindmg 2 and an armature winding 3 operatively associated with thepolyphase line 4. Thefield winding 2 is arranged to be supplied withcurrent from an exciter 5 through an adjust-able resistor 6. The exciter5 comprises an armature winding 7 and a field winding 8 adapted to beconnected in series 1 with a field resistor 9 between the exciterairmatur'e terminals. The efiective resistance of the :exciter fieldcircuit is regulated in accordance with the .voltage of thepolyphasegjine 4. This result is accomplished -through a transformer 10hav ng its pri- .mary' winding 11 connected to the polyphase line 4 andits secondary winding associated with one or more space dischargedevices of the thermionic type or electron discharge I "tubes throughWhlCh a plurality of relays ments 17 and 18,'each ada ted tobe sup-lplied with heating current i rom a different section of the secondarywinding 14. -A resistor 19 is connected in series with the fila ment 17and a like resistor 20 is connected in 68 series with the filament 18. 5

Current from the tubes 12 and 13 is supplied to a relay 21 comprising acoil 22 and an armature 23. The relay 21 is provided to controloperation of the relays 24 and 25 '10 which are arranged toshort-circuit different portions of the exciter field rheostat 9. Therelays 24 and 25 are provided with operating coils 26l and 27 arrangedto operatethe 'armatures 28 and ,29 respectively. When 7 the coil 26 isnot energized, the armature 28 rests upon the memberv 30 which ispivoted at the point 31 and is held against the premure of a spring 32to cause engagement of the relay contact 34. When the coil 26 0o isvenergized, the armature 28 is raised and the contact 34 is disengaged bythe spring 32. The operation of the relay 25 is similar to that of therelay 24 and will be readily understood without 'further' explanation.ll If desired, the relays 24 and 25 may be designed to have difierentdegrees of sensitivity so that they operate in succession to shortcircuit different portions of the rheostat 9.

The armature 23 of the relay 21 is operatively associated with a'member35- ivoted at the point 36 and provided at its le hand. end with acontact 37 arranged to cooperate with a contact 38 for controllin the.con- 96 nection of the relay coils 26 an 27 to the armature terminals ofthe exciter 5. The member is also provided with a back contact 39 forcontrolling the resistance connected in series with filaments of thetubes 12 and 13 to prevent hunting in a manner hereinafter explained.

The operation of my invention will now be readily understood. If thevoltage of the line 4 is slightly below normal, the relays 21,

24 and 25 will besin the positions indicated and all of the resistor 9will be excluded from the field circuit of the exciter 5. Under theseconditions, the excitation of the ma chine 1 is a maximum and thevoltage of the line 4 will tend to rise. If this voltage ex ceeds itsnormal value, sufficient current to raise the armature 23 and close thecontacts '37 and 38 is supplied through the tubes 12 and 13 to the coil22. When this occurs, the coils of the relays 24 and 25 areenergized andthe more sensitive of these relays, relay 24 for example, is opened toincrease the resistance of the exciter field circuit.

and the exciter field circuit resistance is raised to its maximum value.The efiective resistance of the exciter field circuit is determined bythe vibratory action of the relays 21, 24 and 25. These relaysare'designed to respond to slight variations from the normal voltage ofthe line 4 and by the rapidity of their vibration determine theproportion of time during which the exciter field resistor .is shortcircuited. In this manner, variations in the voltage of'the line 4 aremaintained within narrow limits. J r

The relay 21 functions both to control energization of the relays 24 and25 and to actuate anti-hunting means comprising filamentresistors 19 and20 and back contact ing, v p

6. A regulating system of the type where- 39 throughwhich theseresistors are altogether or partially'short-circuited when the relay 21is in its illustrated open position. Upon closure of the relay 21, theresistance of the filament circuit is increased. This reduces thecurrent supplied through the tubes to the operating coil 22 andaccelerates the opening of the relay 21, thereby anticipating abnormalpulsations in the voltage of the line and preventing hunting. J

What I claim as new and by Letters Patent of the United States is:

1. An electric circuit regulator comprisin a relay for causing a changeto be produce in anelectrical condition of a circuit to be regulated, anelectron discharge device con-' nected to respond to variations in theelectrical condition of said circuit'for controlling desire to securethe actuation of said relay, and means operable in response to actuationofsaid relay for controlling said device to prevent huntmg.

2. A regulator for an electric circuit comprising a relay for causing achange to be produced in an electrical condition of said circuit, a hotcathode tube operably associated with said circuit for controlling theactuation of said relay in accordance with variations in the electricalcondition of said circuit, and means operable in response to actuationof said rela for changing the temperature of the cat ode of said tubefor preventing hunting.

' 3. An electric circuit regulator comprising a relay for causing achange to be produced in an electrical condition of said circuit, avacuum tube including a, filament operably associated with said clrcuitfor controlling the actuation of said relay, and a back contact arrangedto cooperate with said relay and said tube for increasing thefilamentcircuit resistance of said tube in response to actuation ofisaid relay.

4. The combination of an electric circuit, a dynamo electric machineoperably associated with said circuit and an exciter for supplying thefield excitation of said .machine, means for regulatingsaid circuit,said means comprising a relay for regulating the field current of saidexciter, electron discharge means operably associated with said circuitfor controlling the actuation of said relay, and means operable inresponse to actuation of said relay for controlling said electrondischarge means to prevent hunting.

5. A regulating system of the type wherein. a vibratory relay isarranged to control a condition to be regulated, an electron dischargedevice connected to vary the energization of said relay in accordancewith variations in said ondition, and means controlled by said relay forcontrolling the amount of electron discharge to vary the energization ofsaid relay to prevent huntin a relay isarranged to control a conditionto be regulated, a space discharge device of the thermlonic type forcontrolling the energization of said relay in accordancewith trollingthe energization of said means, a

hot cathode device arranged to have its plate voltage and cathodetemperature controlled 1n accordance with said condition, and meanscontrolled by said relay to vary the effect of said condition on saidtemperature.

1,esa,ea1

8. A re latinfg system wherein means are provided dr regulating anelectrical condition of a circuit, comprising arelay for controlling theenergization of said means, a

5 hot cathode device for controlling the actuation of said relay, meansincluding a transformer connected to said circuit to control the platevoltage and cathode temperature of said device in accordance 'with saidcondition, and means controlled b said relay to vary 10 the effect ofsaid condi'tlon on said temperature.

In witness whereof, I have hereunto set my hand this 19th day of April1994.

LOUIS w. THOMPSON.

